Thermoelectric string, panel, and covers for function and durability

ABSTRACT

A thermoelectric device comprising an elongated panel of two foam layers, and having an inserted thermoelectric string is incorporated into a seat cushion, planting pot, and battery thermal manager. Several enhancements to the string and the panel improve its durability, visual appeal, and tactile appeal over the prior art.

CROSS-REFERENCE

This application is a continuation of U.S. application Ser. No.14/530,360, filed Oct. 31, 2014, which claims priority to U.S.Provisional Application No. 61/899,665, filed Nov. 4, 2013, U.S.Provisional Application No. 61/939,619, filed Feb. 13, 2014, and U.S.Provisional Application No. 62/019,849, filed Jul. 1, 2014, whichapplications are incorporated herein by reference in their entiretiesfor all purposes.

BACKGROUND OF THE INVENTION

In our earlier U.S. patent application Ser. No. 13/101,015 filed May 4,2011 and Ser. No. 13/394,288 filed Mar. 5, 2012 and PCT ApplicationSerial No. PCT/US11/51227 filed Sep. 12, 2011 and PCT Application SerialNo. PCT/US13/050378 filed Jul. 12, 2013, we describe a thermoelectricheating and cooling system comprising a connected string ofthermoelectric elements woven into an insulating panel, which may becomprised of a soft material like foam, memory foam, batting, or naturalfabrics. A conductor material is expanded on either side of the panel todistribute heat on one side and cooling on the other. Such a material orsurface upgraded with thermoelectric heating and cooling in this manneris called a distributed thermoelectric panel. In our earlierapplications, integration of that insulating panel with mattresses,chairs, and blankets was also described. The end result was a relativelylow cost, distributed heating and cooling addition to bedding, seats,blankets, electronics, and other products.

SUMMARY OF THE INVENTION

The present invention provides various enhancements and improvements toheated and cooled products and their components over the prior art. Thepresent invention introduces new designs for heated and cooled officecushions, battery thermal management systems, and plant soil temperaturecontrol systems. In addition, the present invention providesimprovements to the design of the thermoelectric string that increasesdurability of the office cushion and other improvements that increasethe cushion's tactile and visual appeal.

More particularly, in accordance with the present invention, we providea heated and cooled office cushion for improving comfort and savingenergy, a heated and cooled planting pot for controlling soiltemperature and improving plant productivity, and a battery thermalmanagement system for improving battery power and safety. We alsoprovide various designs of strain reliefs for the thermoelectric stringthat increase its durability when combined with a seat cushion and usedfor long periods. Finally, we provide patterned designs of the cushion'scover and foam surface to improve both tactile feel and visualappearance of the cushion.

More particularly, we provide a thermoelectric cooling device comprisinga thermoelectric string inserted into a multi-layer foam stack wherein afirst layer is optimized for softness and a second layer is optimizedfor softness and airflow combined. In one embodiment, the thermoelectriccooling device is incorporated into a seat cushion including a fan andelectrical power source.

In one embodiment the device includes one or more of the followingfeatures: a battery for temporary cordless operation, an occupancyswitch that turns off the device when not in use, a means for varyingmagnitude and polarity of the voltage or current applied to thethermoelectric string, an electronics enclosure.

In another embodiment the device allows the airflow to exit in multipledirections to compensate for blockage in one direction.

In yet another embodiment the second layer has pillars to allow airflowtherebetween. In such embodiment the pillars' cross-section preferablyis circular, square, hexagonal, or octagonal. Also, the pillarspreferably are formed by molding, by routing, or by linear wire cutting,wherein the wire cutting preferably employs a hot wire, an abrasivewire, or a vibrating wire. Also, if desired, the pillars may bestaggered from one row to a next row to maximize uniformity of airflow.

In one embodiment the thermoelectric string further comprises a strainrelief to prevent breaking of the string's wires during repeated andlong term use. In such embodiment the strain relief preferably is a foamplug that encapsulates the thermoelectric elements and has channels forthe string's wires to exit the plug, wherein the foam plug preferablyhas a Y cut shape or a drilled hole. In another embodiment the devicecomprises tubing and flaps or nipples of latex, rubber, silicone,Teflon, polyurethane, or plastic, optionally combined with anothermaterial to insulate the link wires that connect the thermoelectricelements.

In yet another embodiment the strain relief comprises tape attachedalong the string and extending beyond the thermoelectric elementswherein the tape is comprised of foam, rubber, plastic, Teflon, gel, ora solidifying liquid. In such embodiment, the tape preferably includesfibers for increasing its tensile strength wherein the fibers are glass,nylon, or cloth.

In another embodiment the strain relief comprises cloth woven togetherwith the wire strands.

In another embodiment a plane of the thermoelectric elements andemanating wires in the first foam layer intersects a surface of thedevice at an angle substantially less than 90 degrees.

In such embodiment, the thermoelectric elements preferably are placeddirectly above the pillars or above and between the pillars.

In another embodiment, the strands of the woven wire on the surface areshaped to increase their ability to lengthen or otherwise move understress.

In another embodiment the wires of thermoelectric string are placed inthe foam layers such that stress cycles during use avoid a plasticdeformation regime of the bending of the wires.

Alternatively, the thermoelectric elements are placed underneath a flapof foam in the first foam layer.

In one embodiment material is added between the stranded wires along thesurface to make the surface smoother. In such embodiment the materialpreferably is matched in firmness or profile height or both to thestranded wires.

In one embodiment the device is covered by a textured materialcomprising textile, rubber, vinyl, leather, or other seat coveringmaterial. In such embodiment the texture is formed by embossing, oradditional stitching. Also, in such embodiment the dimensions andseparation of the texture features preferably closely match dimensionsand separation of the stranded wires,

In one embodiment, the device is incorporated into the perimeter of apot containing soil for plants.

In such embodiment the thermoelectric panel preferably is sandwichedbetween two walls of the pot, and airflow optionally is outside thesandwich of either natural or forced convection. In one embodiment, thedevice is incorporated into the outside of a battery for thermalmanagement, or is combined with a heat spreader to move the airflowlayer to another location. In such other embodiment, the heat spreaderpreferably comprises fluid flow or phase change materials.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A, 1B, 1C and 1D show the interior parts of a low-cost cushionfor use in offices and homes to improve comfort and save energy oncentral heating and cooling.

FIGS. 2A and 2B show the two-layer foam construction comprising theinsulating panel and the airflow layer for use in the cushion.

FIGS. 3A and 3B show simulation results of the airflow distribution fortwo designs of the airflow layer for use in the cushion.

FIGS. 4A and 4B show how round pillars for the airflow layer may beapproximated by making linear cuts to the foam in the airflow layer foruse in the cushion.

FIGS. 5A, 5B, 5C, 5D and 5E show various designs for strain relief ofthe thermoelectric string to improve its durability when combined withthe cushion and used for a long period of time.

FIGS. 6A, 6B, 6C, 6D, 6E, 6F, 6G and 6H show a modified configurationfor the thermoelectric string to improve its durability when combinedwith the cushion and used for a long period of time.

FIGS. 7A, 7B and 7C show methods for using existing materials in thethermoelectric panel, or adding new materials, to make the surfacesmoother for increased visual appearance and tactile feel when combinedwith the cushion.

FIGS. 8A and 8B show textured covers for decoratively hiding theirregular surface appearance and feel of the thermoelectric string whencovering the cushion.

FIGS. 9A and 9B show how plant productivity is improved by controllingits soil temperature and lists the some of the plants that benefit fromsoil temperature control.

FIGS. 10A, 10B, 10C and 10D show an embodiment of the present inventionthat achieves heating and cooling of soil in a planter pot.

FIG. 11 shows a thermoelectric panel and airflow system for heating andcooling a battery to control its temperature.

FIGS. 12A, 12B, and 12C show how a thermoelectric panel may be combinedwith a heat spreader to aid in moving the airflow system to the side ofthe panel.

DETAILED DESCRIPTION OF THE INVENTION

In a prior PCT Application Serial No. PCT/US13/050378 filed Jul. 12,2013, the inventors described how an array of foam pillars underneath athermoelectric panel could allow for airflow across heat exchangers madefrom braided or stranded wire. The pillars, attached to the insulatingfoam layer, permit independent vertical movement thereby distributingpressure evenly. The inventors shown in PCT Application Serial No.PCT/US13/050378 filed Jul. 12, 2013 that this construction could retainthe pressure distribution characteristics of whatever cushioning wasunderneath, which is a significant feature for a generalizedheating/cooling layer that may be applied to a variety of surfaces.

In this application, we show methods for manufacturing the pillars andoptimizing their shape, protecting the wire and thermoelectric elementsfrom cyclic stress, smoothing the surface, and constructing an entireheated and cooled cushion using a small number of parts with lowmanufacturing costs.

FIGS. 1A-1D show the internals of a completed form-factor cushion. FIG.1A shows the two layers 101 and 106 of foam arranged as described in PCTApplication Serial No. PCT/US13/050378 and having the thermoelectricstring 103 inserted into the top layer, and pillars 106 in the bottomlayer. The heat exchangers 107 made from stranded wire are exposed inthe airflow layer as shown in the underside view of FIG. 1C. The redbutton 108 in the center of FIG. 1C is a pushbutton switch that acts asan occupancy switch to turn on the heating or cooling when a user issitting or lying down on the cushion. Without limitation, an occupancysensor could replace the switch. Such a sensor inputting to controlelectronics could perform the same function.

FIG. 1B shows the electronics enclosure 102 at the back of the cushionseparated from the panel. This enclosure contains or may contain thefans 109, airflow ducting 105, control electronics, wiring 104, powerconnectors, switches, knobs, and batteries. The fans 109 pull air 105from the front of the cushion shown by the arrows in FIG. 1A. As shownin FIG. 1C, the fans push the air 105 upward but diagonally away fromthe user assuming the user is in the sitting position as shown in theclose up view in FIG. 1C.

FIGS. 2A-2B show two views of a manufactured, dual-layer foam stack withone layer 112 and 106 patterned with pillars. First, the optimum type offoam for the continuous layer 111 is selected for comfort and feel, asthis layer will become the foam surface of the cushion. Next, theoptimum type of foam for the pillared layer 112 and 106 is selected toallow airflow when under pressure of the user. To begin the manufacture,two continuous layers of each type of foam are bonded together. Then,the pillars are formed. FIGS. 2A-2B show the pillars formed using arouter machine, which routs out the channels between the pillars.Without limitation, the pillars can also be formed using a hot wire cutmachine, wherein the hot wire traverses a U shaped path to construct achannel. Without limitation, many hot wires could be employedsimultaneously to increase throughput. Also without limitation, thepatterned pillars 106 and 112 in FIGS. 2A-2B could be formed in a moldas the foam is produced. The continuous layer 111 could be formed inplace on top of the pillared layer 112 and 106, or be bonded afterwards.

Analysis and simulations performed by the inventors indicate that squarepillars 106 like the ones in FIGS. 2A-2B are not the optimal shape forairflow. Staggered round pillars 106 allow more uniform airflow 105, asindicated in the computer-aided analysis illustrated in FIGS. 3A and 3B.

FIGS. 4A-4B show how a round pillar may be approximated using a hot wirecut machine. FIG. 4A shows how 4 hot-wire cut directions along thedotted lines can form octagonal pillars 106 with remaining foam basematerial 112. FIG. 4B shows how 3 hot-wire cut directions along thedotted lines can form hexagonal pillars 106. Without limitation, the hotwire cut operation could be replaced with an abrasive wire saw orvibrating operation.

FIGS. 5A-5E show many different design enhancements to the basethermoelectric string to protect the wires from breakage after repeatedbending cycles when in the cushion after numerous sitting cycles. Theobjective of these enhancements is to limit the bend radius of the wireduring the bending cycles. It has been known for a long time in theindustry that putting a lower bound on the bend radius of a wire canincrease its bend cycle life by several orders of magnitude.

FIG. 5A shows a closed-cell foam plug in the shape of a cylinder 201.Without limitation, the plug may have a Y shape cut in the side forplacement of the thermoelectric junction. Or, the plug may have a holein the center and the junction inserted into the hole from above. The Ycut or the hole allows a path for the two links 202 and the one loop 204of the thermoelectric junction to exit the foam plug. The hardness ofthe foam is selected to result in a gradual but not severe bending ofthe wire under compression from directly above. The attachment of thewire to the junction is protected inside the foam plug by preventingacute bending at this location. Without limitation, the material usedfor this purpose could be closed cell foam, open cell foam, Styrofoam,rubber, plastic, or gel.

FIG. 5B shows another method for protecting the thermoelectric string.Here, a length of latex tubing 205 is cut partway down to form twoflaps. The flaps protect the two links leaving the junction, and thetubular portion protects the loop's attachment to the junction. Withoutlimitation, this material used for this purpose could be silicone,polyurethane, plastic, Teflon, gel, or any other similar material.

FIG. 5C shows another method for protecting the thermoelectric string.Here, lengths of fiberglass tape 206 are attached to the outside of thejunction and extend along the loop and along the link to beyond the 90degree angle at the surface. The tape adhered to the wire and junctionforces a mild bend radius at all points where the tape is present.Without limitation, the material used could be foam tape, rubber tape,electrical tape, woven plastic tape, plastic tape, Teflon tape, geltape, or any other similar material with adhesive or without such asliquid plastics that solidify after placement.

FIG. 5D shows another method for protecting the thermoelectric string.Here, a latex nipple 207, similar to those used in baby bottles, is usedto limit the bend radius and protection the wire-to-board attachments. Afoam plug 208 is used to maintain electrical insulation between thelinks. The loop wire is routed through a hole at the narrow end of thenipple. The links are routed over the wide end of the nipple. Withoutlimitation, this nipple shape could be made of silicone, polyurethane,rubber, plastic, Teflon, gel, or any other similar material.

FIG. 5E shows a length of stranded wire 209 that is combined with clothfibers to improve the tensile strength of the links and reduce thebending stress on the wires. When the cushion has the weight of aperson's torso, the compression lengthens the surface of the foam, whichin turn puts tensile stress on the links.

Now, we generalize the design of the thermoelectric ribbon further in away that durability is achieved and is predictable. The physical processof metal wires flexing and then breaking is rooted in the repeatedweakening of each bend. If the wire's strength is weakened even slightlyon each cycle of stress, then breakage is likely to occur after the3,000 to 100,000 stress cycles required for the durability of a consumerproduct. The slight weakening of a metal wire on each flex can bepredicted by looking at its deformation. If the wire's original shapereturns after the flex, then the deformation is elastic. If the wire'sshape changes after the flex, then the deformation is plastic. Plasticdeformation of a wire changes its physical properties and weakens thewire. Repeated plastic deformation of a wire is certain to lead tobreakage. Repeated elastic deformation of a wire will last much longer.Plastic or elastic deformation is observable on a thermoelectric ribboninserted into a panel on the first cycle of a durability test. Hence,the nature of the deformation on the first cycle of a thermoelectricpanel is predictive of its durability. Further, a thermoelectric panelcan be designed to only incur elastic deformation or to avoid plasticdeformation, or both, as verified in the first cycle or a small numberof cycles of a durability test.

FIGS. 6A-6D show two designs of the thermoelectric ribbon, as it wouldappear in a panel. The panel is not shown for illustrative purposes.FIG. 6A is the traditional design with vertical junctions 210 inside thepanel, horizontal links 202 along the surface of the panel, and curledheat exchangers underneath the junctions positioned in an airflow layer.After applying compression to this ribbon with an equivalentdisplacement of the standard durability test, the wires in the ribbonbecome plastically deformed as shown in FIG. 6B.

FIG. 6C shows the end view of the angled design, wherein the planecontaining the lines of the junctions 210 intersects at a 45-degreeangle the plane of the links 202 along the surface. FIG. 6D shows thestring after a stress cycle that compressed the ribbon to a very narrowvertical clearance. The resting shape of the ribbon in FIG. 6D aftercompression stress has returned to that of FIG. 6C, indicating theabsence of plastic deformation. Without limitation, all designs of athermoelectric ribbon that avoid plastic deformation in a cycle ofstress are covered by this invention.

The angled design of FIG. 6C can be inserted into the foam panel of thecushion 101 in FIG. 1A such that the junction 210 in FIG. 6C ispositioned either above the pillar 106 in FIG. 1A or between thepillars. Placing the junction above the pillar allows the junction to becushioned by the pillar in severe compression. Placing the junctionbetween the pillar allows the wires to bend more freely in the soft foamand hence less susceptible to plastic deformation. Both placementlocations have advantages depending on the stress conditions and thespring constants of the two foam layers.

FIGS. 6E through 6F show how shaping the woven strands in link 202 canmake the system more durable in a stress test. One failure mode of anoffice cushion occurs when the links 202 are forced to lengthen in orderto accommodate the depression made in the foam when a person sits on it.With the fishnet-woven braid in FIG. 6A, the outer strands of the weavedo not have sufficient slack to accommodate the necessary lengthening,which results in tensile stress on the wire strands where they join thejunction. FIGS. 6F through 6H show steps in shaping the links wires toachieve more slack and hence lengthening capability under stress. First,in FIG. 6F, the terminated ends of the link 202 are pushed inwardstowards each other, which creates a bulge on wires surrounding an emptycavity. Next, in FIG. 6G, the bulging section is folded into a Z shape,which shortens the length from termination to termination of the link.Then, the fold is flattened to achieve the final shape in FIG. 6H. Notehow in FIG. 6H the fold lessens as the ends of the link are pulled awayfrom each other. This slack in the link allows for further lengtheningunder stress of a person sitting on a cushion with these links 202 onthe surface.

As previously mentioned, maintaining a radius of curvature of the wiresis critical to prevent the wires from breaking under repeated sittingcycles of the thermoelectric panel in a cushion. Furthermore, it isdesirable to make the foam surface as smooth as possible for tactile andvisual appeal. FIGS. 7A-7C show a low-cost method for protecting thewire as it turns along the surface and additionally for smoothing thesurface. A flap 301 is cut in the foam as shown in FIG. 7A using aU-shaped blade inserted at an angle to the surface. The flap 301 of foamis lifted up and the thermoelectric junction is inserted through to theairflow layer. Then the flap 301 is returned to it original position asshown in FIG. 7B. Now, the presence of foam both above and below thewire 202 at the point where it turns 90 degrees along the surface limitsthe curvature under pressure stress or rolling stress. This method ofusing the flap also reduces the “egg-crating” irregularity of thesurface, which naturally results from the wire 202 being routed into andout of the surface foam. The surface of FIG. 7B is still irregularbecause of the profile height and rigidity of the wires 202 are elevatedfrom the foam surface. This irregularity is easily seen and felt throughmany different types of covers. A thick cover can reduce thisirregularity, but thick covers also degrade the thermal performance ofthe panel. Hence, a better solution is needed to smooth the surfacewithout introducing thermal resistance. FIG. 7C shows such a method forsmoothing the surface. A material 302 with the similar profile heightand rigidity as the wire 202 is placed around the wire. In FIG. 7C, thematerial is a canvas cloth. Without limitation, any material thatmatches the height of the woven wire could be used. The material may bestretchy to match the hammock deformation of the underlying cushion whenin use. The material may be made from, without limitation, a solidpolyurethane sheet, tape, spandex cloth, closed cell foam sheet, orother suitable material.

In all of the embodiments of the thermoelectric panel in this andprevious patent applications, the link wires along the surface are mosteffective when in close proximity to the skin of the person being heatedor cooled, i.e. when the cover over the wires is thin. However, a humanhand can feel these wires through a smooth thin cover and this tactilefeel is undesirable. And, some covers will stretch over the wires duringuse and remain permanently stretched with an apparent bagginess patternto the cover over time. Designs of covers that address these issues arecovered in FIGS. 8A-8B.

FIG. 8A shows an embossed bed cover 401 and a stitched textile pattern402, which could be used as a cover over a thermoelectric panel. Thiscover is made from a thin material, like a bed sheet fabric, but theembossing or stitching creates peaks and valleys in the surface contour.A human hand moving along a thermoelectric panel with this cover willnot be able to distinguish the embossed or stitched peaks and valleyswith the feel of the wires underneath, especially and withoutlimitation, if the spacing and size of the embossed or stitched featuresis comparable with the spacing and size of the wires. These covers alsovisually create a pattern that is visually indistinguishable from anypattern of bagginess from the cover stretching over the wires that mightoccur over time. And, because the embossed fabric 401 flattens under theweight of a person and the area of the stitching in 402 is very small,the net thickness during use is very thin. Hence, these patternedfabrics address the issues with the wires under the cover, optimizingthe visual appearance, the tactile feel, and the thermal performance.FIG. 8B shows several embossed patterns for leather. Again, the embossedfeatures flatten out under the weight of a person, allowing for goodthermal conduction in the contact area.

Another application for a thermoelectric string, panel, and possiblyairflow layer is for controlling the temperature of soil for plants.FIG. 9A shows that the productivity of plants is a strong function ofthe soil temperature. Plants typically categorized as “cool season”plants have productivity profile 501, “temperature season” plants haveproductivity profile 502, and “warm season” plants have profile 503.These three profiles have optimal soil temperatures of approximately 65F, 75 F, and 85 F respectively. FIG. 9B shows a list of plants in thesethree categories. It is desirable to grow warm season plants in thewinter and cool season plants in the summer, and to be able to growmixed combinations of plants in a single environment. Controlling soiltemperature enables optimization of plant productivity and flexibilityin the thermal environment of the plants.

FIG. 10A shows a plant pot containing soil wherein the temperature ofthe soil is controlled by a thermoelectric string and panel. Aninsulating top layer 504 is needed to prevent heat transfer through thetopsoil, and this layer could be made of decorative pumice stone orother material with good insulating properties. The pot consists of aninner wall 505 and an outer wall 506. Between these two walls is athermoelectric panel. The apparatus of FIG. 10A does not contain anairflow layer, as natural convection removes heat from wall 506 when thesoil is being cooled. By reversing the electrical current in thethermoelectric panel, the soil is warmed instead of cooled. Thetemperature probe in FIG. 10B shows that the soil near the side 506 is67.4 F; FIG. 10C shows that the temperature of the soil in the center ofthe pot is 70.0 F and the ambient temperature is 79.6 F. Thesetemperature readings were taken in steady state conditions and show thatthe soil is cooled by about 10 degrees F. from ambient by thethermoelectric panel, meeting the requirement to cover optimumtemperature range of + or −1° F. shown in FIG. 9A. FIG. 10D shows thatthis result was accomplished by applying 6.3 volts and 2.11 amps to thethermoelectric panel, which included a thermoelectric string of 85junctions.

Yet another application of a thermoelectric string, panel, and possiblyan airflow layer is thermal management of batteries. Battery temperatureneeds to be controlled for three reasons: efficiency, lifetime, andsafety. FIG. 11 shows how the a thermoelectric string 202 and 210 is inthermal contact with a battery 602 on one side and possibly an airflowlayer on the other side that contains moving air 105. Alternatively, acold plate that is in thermal contact with the loop wires could replacethe airflow layer. An insulated container 601 is added if thetemperature outside the battery is adversely affecting its temperaturein the regions beyond the thermoelectric panel.

Many applications for thermoelectric panel are challenged in having theairflow layer covering one whole side of the panel. In seating andbedding, for example, forming an airflow layer underneath the panel andunder the weight of the user presents design and form-factor challengesin some cases. In these cases, it is helpful to have a heat spreaderthat can move the excess heat to another location that is moreconvenient for the airflow layer or other heat exchanger. FIG. 12Aillustrates a thin plate 701 with a moving fluid inside that moves heatvery effectively from the flat area to the sides. FIG. 12B shows anactual product from ThermAvant Technologies, Inc. that spreads heatusing this method. In FIG. 12C, this heat spreader 701 is mountedunderneath, and in thermal contact with, the thermoelectric panel 111.Because of the spreader 701 essentially conducts heat very effectively,the airflow 105, or other heat exchanger, may be moved to anotherlocation. In FIG. 12C, this new location is at the end of the spreader701.

Without limitation, the inventions described herein can be applied toseats, seat backs, seat tops, bed tops, wheelchair cushions, hospitalbeds, animal beds, and office chairs.

What is claimed is:
 1. A thermoelectric device comprising a plurality ofthermoelectric elements and a plurality of thermoelectric strings,wherein said plurality of thermoelectric elements are in at least onelayer of foam in a manner such that said plurality of thermoelectricstrings have reduced susceptibility to deformation, wherein saidplurality of thermoelectric strings comprises strings in a folded-overconfiguration away from said plurality of thermoelectric elements andadjacent to a surface of said at least one layer of foam, wherein saidplurality of thermoelectric elements are disposed in a first plane andsaid plurality of thermoelectric strings are disposed in a second plane,wherein said first plane intersects said second plane.
 2. The device ofclaim 1, further comprising an electrical power source in electricalcommunication with said plurality of thermoelectric elements.
 3. Thedevice of claim 1, further comprising a strain relief element that isconfigured to provide strain relief to a thermoelectric string of saidplurality of thermoelectric strings.
 4. The device of claim 3, whereinsaid strain relief element is insulated from said plurality ofthermoelectric strings.
 5. The device of claim 3, wherein: (a) saidstrain relief element is a foam plug that encapsulates said plurality ofthermoelectric elements and comprises channels for said plurality ofthermoelectric strings to exit said plug; (b) said strain relief elementis a Y-shaped foam plug or a drilled hole; (c) said strain reliefelement comprises tubing and flaps or nipples formed of a polymericmaterial; (d) said strain relief element comprises a tape attached alongsaid plurality of thermoelectric strings and extending beyond saidplurality of thermoelectric elements; (e) said strain relief elementcomprises tape that includes fibers for increased tensile strength ofsaid tape; or (f) said strain relief element comprises fibers woventogether with said plurality of thermoelectric strings.
 6. The device ofclaim 5, wherein said polymeric material comprises latex, rubber,silicone, Teflon, polyurethane, or plastic.
 7. The device of claim 5,wherein said tape is formed of foam, rubber, plastic, Teflon, gel, or asolidified liquid.
 8. The device of claim 5, wherein said fibers areformed of glass, nylon or cloth.
 9. The device of claim 1, wherein saidplurality of thermoelectric strings comprises links of woven wires. 10.The device of claim 9, wherein said folded-over configuration includesmultiple folds of said links of said plurality of thermoelectricstrings.
 11. The device of claim 1, further comprising a materialbetween at least a portion of said plurality of thermoelectric stringspositioned along said surface of said at least one layer of foam. 12.The device of claim 1, further comprising a textured material coveringsaid at least one layer of foam.
 13. The device of claim 1, furthercomprising a heat spreader configured to facilitate movement of excessheat away from said at least one layer of foam.
 14. The device of claim13, wherein said heat spreader comprises fluid flow or phase changematerial.
 15. The device of claim 1, further comprising an occupancyswitch that regulates supply of power to said plurality ofthermoelectric elements for heating or cooling.
 16. The device of claim1, further comprising an enclosure having said at least one layer offoam.
 17. The device of claim 1, wherein said plurality ofthermoelectric stings are disposed in a flap of foam in said at leastone layer of foam.
 18. The device of claim 1, wherein said at least onelayer of foam comprises a plurality of layers of foam.
 19. The device ofclaim 1, wherein said deformation is plastic deformation.